The long-term impact of eGFR reporting on referral patterns.

BACKGROUND: The prognostic significance of CKD has driven the widespread introduction of automated estimated glomerular filtration rate (eGFR) reporting, and the incorporation of CKD in the revised Quality Outcomes Framework (QOF) of the General Medical Services (GMS) contract in the U.K. AIMS: To assess the long-term impact of the introduction of these two initiatives, on patient referral numbers to a nephrology service. METHODS: Data was collected on the numbers and basic characteristics of all new patients referred from April 2005 to March 2011, to one NHS Health Board. RESULTS: Introduction of eGFR reporting and CKD QOF domains was associated with a significant increase in the number of referrals, which was sustained. The initiatives also led to a sustained increase in the mean age of the patients at referral, predominantly due to an increase in the age of female patients referred. There was also an increase in the proportion of female patients referred. In the immediate aftermath of the introduction of change there was a transient decrease in the average eGFR at referral, a decrease in age of patients referred with an eGFR <15ml/min and an increase in the eGFR of patients >70yrs of age. CONCLUSIONS: The data demonstrates significant and sustained increase in numbers of referrals. In the short term this was associated with a reduction in referral of elderly patients with stage 5 CKD and an increase in elderly patients with mild renal impairment. In the longer term we saw an increase in referral of an older female population.

Severe hyperkalaemia: demographics and outcome.

BACKGROUND: Few studies have evaluated the prevalence of severe hyperkalaemia in unselected patient populations. We identified all episodes of severe hyperkalaemia occurring in 1 year, and described patient demographics, clinical response and outcome. We also assessed junior doctor knowledge of its causes and significance. MATERIALS AND METHODS: A retrospective interrogation of the database of the regional biochemical laboratory identified all episodes of severe hyperkalaemia (K≥ 6.5 mmol/L) occurring in 2011. The understanding of trainee doctors of the importance, causes and treatment of severe hyperkalaemia was assessed by structured questionnaire. RESULTS: Severe hyperkalaemia was recorded in 433 samples (365 patients) giving a prevalence of 0.11%. Thirty-six per cent of episodes occurred in patients under the care of a nephrologist, who were significantly younger than those not under the care of a nephrologist. In the nephrology cohort, 86% occurred in patients with chronic kidney disease (CKD), the majority of which had CKD Stage 5. In the non-nephrology cohort, only 65% occurred in the context of CKD, which was equally distributed between Stages 3 and 5 CKD. In both patient groups, roughly 50% of episodes occurred in association with acute kidney injury (AKI). Acute mortality (death within 48 h of documented severe hyperkalaemia) was higher in the non-nephrology compared with the nephrology cohort. Time to repeat serum potassium was influenced by the clinical setting with shorter time to repeat for acute care compared with ward settings. Assessment of trainee doctor's knowledge suggested significant deficiencies in relation to severe hyperkalaemia. CONCLUSIONS: The prevalence of severe hyperkalaemia was low and occurred predominantly in the context of CKD and/or AKI. The majority of episodes occurred in patients not under the care of a nephrologist. Variability in time to repeat serum potassium levels suggested deficiencies in care, and assessment of trainee doctor's knowledge suggests the need for further educational initiatives to highlight its importance.

Identifying primary stressors impacting macroinvertebrates in the Salinas River (California, USA): relative effects of pesticides and suspended particles.

Laboratory dose-response experiments with organophosphate and pyrethroid pesticides, and dose-response experiments with increasing particle loads were used to determine which of these stressors were likely responsible for the toxicity and macroinvertebrate impacts previously observed in the Salinas River. Experiments were conducted with the amphipod Hyalella azteca, the baetid mayfly Procloeon sp., and the midge Chironomus dilutus (Shobanov, formerly Chironomus tentans). The results indicate the primary stressor impacting H. azteca was pesticides, including chlorpyrifos and permethrin. The mayfly Procloeon sp. was sensitive to chlorpyrifos and permethrin within the range of concentrations of these pesticides measured in the river. Chironomus dilutus were sensitive to chlorpyrifos within the ranges of concentrations measured in the river. None of the species tested were affected by turbidity as high as 1000 NTUs. The current study shows that pesticides are more important acute stressors of macroinvertebrates than suspended sediments in the Salinas River.

A comparison of in situ and laboratory toxicity tests with the estuarine amphipod Eohaustorius estuarius.

Amphipod survival in laboratory and in situ exposures was assessed using the eastern Pacific Haustoriid species Eohaustorius estuarius. Toxicity test results were compared using intact (unhomogenized) and homogenized sediment samples in both field and laboratory exposures. Experiments were conducted in Moss Landing Harbor, California, an impaired waterbody under 303 (d) of the US Clean Water Act. Synoptic laboratory and in situ sediment toxicity tests were conducted at two stations: Sandholdt Bridge (SB), the most contaminated station in the harbor, and at the South Jetty (SJ), a more marine station near the mouth of the harbor. We found that Eohaustorius is amenable to in situ testing. Despite highly variable field salinity regimes (6-32 PSU at SB and 21-34 PSU at SJ), in situ control survival was 87% and 84% at SB and SJ, respectively. Amphipod survival was lower in the in situ exposures relative to the laboratory exposures at both sites. Survival at SB was 30% and 76% in the homogenized in situ and laboratory samples, respectively, and 40% and 64% in the intact (unhomogenized) in situ and laboratory samples, respectively. Neither the homogenized or intact samples from the SJ station were toxic in laboratory experiments, but amphipod survival was only 40% in the intact in situ exposure at this station, possibly due to predation. These experiments suggest that the interaction of contaminants and variable physical parameters such as salinity and temperature may have resulted in lower survival in the in situ exposures. Sediment homogenization prior to in situ deployment may have reduced effects of predators in some samples.

Integrated assessment of the impacts of agricultural drainwater in the Salinas River (California, USA).

The Salinas River is the largest of the three rivers that drain into the Monterey Bay National Marine Sanctuary in central California. Large areas of this watershed are cultivated year-round in row crops and previous laboratory studies have demonstrated that acute toxicity of agricultural drainwater to Ceriodaphnia dubia is caused by the organophosphate (OP) pesticides chlorpyrifos and diazinon. In the current study, we used a combination of ecotoxicologic tools to investigate incidence of chemical contamination and toxicity in waters and sediments in the river downstream of a previously uncharacterized agricultural drainage creek system. Water column toxicity was investigated using a cladoceran C. dubia while sediment toxicity was investigated using an amphipod Hyalella azteca. Ecological impacts of drainwater were investigated using bioassessments of macroinvertebrate community structure. The results indicated that Salinas River water downstream of the agricultural drain is acutely toxic to Ceriodaphnia, and toxicity to this species was highly correlated with combined toxic units (TUs) of chlorpyrifos and diazinon. Laboratory tests were used to demonstrate that sediments in this system were acutely toxic to H. azteca, which is a resident genus. Macroinvertebrate community structure was moderately impacted downstream of the agricultural drain input. While the lowest macroinvertebrate abundances were measured at the station demonstrating the greatest water column and sediment toxicity and the highest concentrations of pesticides, macroinvertebrate metrics were more significantly correlated with bank vegetation cover than any other variable. Results of this study suggest that pesticide pollution is the likely cause of laboratory-measured toxicity in the Salinas River samples and that this factor may interact with other factors to impact the macroinvertebrate community in the system.

Causes of sediment toxicity to Mytilus galloprovincialis in San Francisco Bay, California.

Since the San Francisco Regional Monitoring Program (RMP) sampling began, elutriate samples prepared with sediment from the Grizzly Bay monitoring station have been consistently toxic to bivalve larvae (Mytilus galloprovincialis). An investigation into the cause of toxicity was initiated with a Phase I Toxicity Identification Evaluation (TIE) using bivalve embryos. TIE results and chemical analyses of elutriate samples suggested that divalent metals were responsible for the observed toxicity. Following the initial characterization of trace metals as toxicants, additional TIEs were performed on elutriates prepared from three additional Grizzly Bay samples collected between 1997 and 2001. Additional TIEs included ethylenediamine tetraacetic acid (EDTA) treatments in a sediment-water interface (SWI) exposure system, and the use of a cation exchange column with serial elution of sample fractions with hydrochloric acid of increasing normality. EDTA significantly reduced toxicity in overlying water in the SWI system. The cation exchange column reduced both toxicity and concentrations of trace metals, and serial elution of the column added back both toxicity and specific metals contained in individual acid fractions. Chemical analyses of three elutriate samples demonstrated copper concentrations were within the range toxic to bivalves. Results of Phase I TIEs, additional Phase II treatments, SWI exposures, and metals analyses indicate the potential for metal toxicity in sediments from this estuarine site. When combined with the results of standard TIE methods, a solid-phase cation extraction and elution approach identified copper as the most probable cause of toxicity.

Causes of ambient toxicity in the Calleguas Creek watershed of southern California.

A combination of toxicity tests, chemical analyses, and Toxicity Identification Evaluations (TIEs) were used to investigate receiving water toxicity in the Calleguas Creek watershed of southern California. Studies were conducted from 1995 through 1999 at various sites to investigate causes of temporal variability of toxicity throughout this system. Causes of receiving water toxicity varied by site and species tested. Investigations in the lower watershed (Revolon Slough, Santa Clara Drain, Beardsley Wash) indicated that toxicity of samples to the cladoceran Ceriodaphnia dubia was due to elevated concentrations of the organophosphate pesticide chlorpyrifos, while causes of intermittent toxicity to fathead minnows (Pimephales promelas) and the alga Selanastrum capricornutum were less clear. Investigations at sites in the middle and upper reaches of the watershed (Arroyo Simi and Conejo Creek) indicated that the pesticide diazinon was the probable cause of receiving water toxicity to Ceriodaphnia. Elevated ammonia was the cause of toxicity to fathead minnows in the upper watershed sites. Results of these and previous studies suggest that biota are impacted by degraded stream quality from a variety of point and non-point pollution sources in the Calleguas Creek watershed. Water quality resource manager's efforts to identify contaminant inputs and implement source control will be improved with the findings of this study.

An evaluation of methods for calculating mean sediment quality guideline quotients as indicators of contamination and acute toxicity to amphipods by chemical mixtures.

Mean sediment quality guideline quotients (mean SQGQs) were developed to represent the presence of chemical mixtures in sediments and are derived by normalizing a suite of chemicals to their respective numerical sediment quality guidelines (SQGs). Mean SQGQs incorporate the number of SQGs exceeded and the degree to which they are exceeded and are used for comparison with observed biological effects in the laboratory or field. The current research makes it clear, however, that the number and type of SQGs used in the derivation of these mean quotients can influence the ability of mean SQGQ values to correctly predict acute toxicity to marine amphipods in laboratory toxicity tests. To determine the optimal predictive ability of mean SQGQs, a total of 18 different chemical combinations were developed and compared. The ability of each set of mean SQGQs to correctly predict the presence and absence of acute toxicity to amphipods was determined using three independent databases (n = 605, 2753, 226). Calculated mean SQGQ values for all chemical combinations ranged from 0.002 to 100. The mean SQGQ that was most predictive of acute toxicity to amphipods is calculated as SQGQ1 = ((sigma ([cadmium]/4.21 )([copper]/270)([lead]/ 12.18)([silver]/1.77)([zinc]/ 410)([total chlordane]/6)([dieldrin]/8)([total PAHoc]/1,800)([total PCB]/400))/9). Both the incidence and magnitude of acute toxicity to amphipods increased with increasing SQGQI values. To provide better comparability between regions and national surveys, SQGQ1 is recommended to serve as the standard method for combination of chemicals and respective SQGs when calculating mean SQGQs.

Influence of sample manipulation on contaminant flux and toxicity at the sediment-water interface.

Toxicities of sediments from San Diego and San Francisco Bays were compared in laboratory experiments using sea urchin (Strongylocentrotus purpuratus) embryos exposed to pore water and at the sediment-water interface (SWI). Toxicity was consistently greater to embryos exposed at the SWI to intact (unhomogenized) sediment samples relative to homogenized samples. Measurement of selected trace metals indicated considerably greater fluxes of copper, zinc, and cadmium into overlying waters of intact sediment samples. Inhibition of sea urchin embryo development was generally greater in sediment pore waters relative to SWI exposures. Pore water toxicity may have been due to elevated unionized ammonia concentrations in some samples. The results indicate that invertebrate embryos are amenable to SWI exposures, a more ecologically relevant exposure system, and that sediment homogenization may create artifacts in laboratory toxicity experiments.

A large-scale categorization of sites in San Francisco Bay, USA, based on the sediment quality triad, toxicity identification evaluations, and gradient studies.

Sediment quality was assessed in San Francisco Bay, California, USA, using a two-tiered approach in which 111 sites were initially screened for sediment toxicity. Sites exhibiting toxicity were then resampled and analyzed for chemical contamination, recurrent toxicity, and, in some cases, benthic community impacts. Resulting data were compared with newly derived threshold values for each of the metrics in a triad-based weight-of-evidence evaluation. Sediment toxicity test results were compared with tolerance limits derived from reference site data, benthic community data were compared with threshold values for a relative benthic index based on the presence and abundance of pollution-tolerant and -sensitive taxa, and concentrations of chemicals and chemical mixtures were compared with sediment quality guideline-based thresholds. A total of 57 sites exceeded threshold values for at least one metric, and each site was categorized based on triad inferences. Nine sites were found to exhibit recurrent sediment toxicity associated with elevated contaminant concentrations, conditions that met program criteria for regulatory attention. Benthic community impacts were also observed at three of these sites, providing triad evidence of pollution-induced degradation. Multi- and univariate correlations indicated that chemical mixtures, heavy metals, chlordanes, and other organic compounds were associated with measured biological impacts in the Bay. Toxicity identification evaluations indicated that metals were responsible for pore-water toxicity to sea urchin larvae at two sites. Gradient studies indicated that the toxicity tests and benthic community metrics employed in the study predictably tracked concentrations of chemical mixtures in Bay sediments.

Evaluation and use of sediment toxicity reference sites for statistical comparisons in regional assessments.

Sediment reference sites were used to establish toxicity standards against which to compare results from sites investigated in San Francisco Bay (California, USA) monitoring programs. The reference sites were selected on the basis of low concentrations of anthropogenic chemicals, distance from active contaminant sources, location in representative hydrographic areas of the Bay, and physical features characteristic of depositional areas (e.g., fine grain size and medium total organic carbon [TOC]). Five field-replicated sites in San Francisco Bay were evaluated over three seasons. Samples from each site were tested with nine toxicity test protocols and were analyzed for sediment grain size and concentrations of trace metals, trace organics, ammonia, hydrogen sulfide, and TOC. The candidate sites were found to have relatively low concentrations of measured chemicals and generally exhibited low toxicity. Toxicity data from the reference sites were then used to calculate numerical tolerance limits to be used as threshold values to determine which test sites had significantly higher toxicity than reference sites. Tolerance limits are presented for four standard test protocols, including solid-phase sediment tests with the amphipods Ampelisca abdita and Eohaustorius estuarius and sea urchin Strongylocentrotus purpuratus embryo/larval development tests in pore water and at the sediment-water interface (SWI). Tolerance limits delineating the lowest 10th percentile (0.10 quantile) of the reference site data distribution were 71% of the control response for Ampelisca, 70% for Eohaustorius, 94% for sea urchin embryos in pore water, and 87% for sea urchins embryos exposed at the SWI. The tolerance limits are discussed in terms of the critical values governing their calculation and the management implications arising from their use in determining elevated toxicity relative to reference conditions.

Statistical significance of sediment toxicity test results: threshold values derived by the detectable significance approach.

A number of methods have been employed to determine the statistical significance of sediment toxicity test results. To allow consistency among comparisons, regardless of among-replicate variability, a protocol-specific approach has been used that considers protocol performance over a large number of comparisons. Ninetieth-percentile minimum significant difference (MSD) values were calculated to determine a critical threshold for statistically significant sample toxicity. Significant toxicity threshold values (as a percentage of laboratory control values) are presented for six species and nine endpoints based on data from as many as 720 stations. These threshold values are useful for interpreting sediment toxicity data from large studies and in eliminating cases where statistical significance is assigned in individual cases because among-replicate variability is small.

Sediment quality in Los Angeles Harbor, USA: a triad assessment.

Sediment quality in the Los Angeles and Long Beach Harbor area of southern California, USA, was assessed from 1992 to 1997 as part of the California State Water Resources Control Board's Bay Protection and Toxic Cleanup Program and the National Oceanic and Atmospheric Administration's National Status and Trends Program. The assessment strategy relied on application of various components of the sediment quality triad, combined with bioaccumulation measures, in a weight-of-evidence approach to sediment quality investigations. Results of bulk-phase chemical measurements, solid-phase amphipod toxicity tests, pore-water toxicity tests with invertebrate embryos, benthic community analyses (presented as a relative benthic index), and bioaccumulation measures indicated that inner harbor areas of this system are polluted by high concentrations of a mixture of sediment-associated contaminants and that this pollution is highly correlated with toxicity in laboratory experiments and degradation of benthic community structure. While 29% of sediment samples from this system were toxic to amphipods (Rhepoxynius abronius or Eohaustorius estuarius), 79% were toxic to abalone embryos (Haliotis rufescens) exposed to 100% pore-water concentrations. Statistical analyses indicated that amphipod survival in laboratory toxicity tests was significantly correlated with the number of crustacean species and the total number of species measured in the benthos at these stations. Triad measures were incorporated into a decision matrix designed to classify stations based on degree of sediment pollution, toxicity, benthic community degradation, and, where applicable, tissue concentrations in laboratory-exposed bivalves and feral fish.

The European Resuscitation Council's paediatric life support course 'Advanced Paediatric Life Support'.

The poor outcome for resuscitation from cardiopulmonary arrest in childhood is widely recognised. The European Resuscitation Council has adopted the Advanced Paediatric Life Support course (originating in the UK and now available in a number of countries) as its course for providers caring for children. This paper outlines the course content and explains its remit, which is to reduce avoidable deaths in childhood by not only resuscitation from cardiac arrest but, more effectively, by recognising and treating in a timely and effective fashion life-threatening illness and injury in infants and children. Two related courses Paediatric Life Support, a less intense course for less advanced providers, and Pre-Hospital Paediatric Life Support for immediate care providers are also described.

Supporting relatives following a cot death.

The incidence of sudden infant death syndrome or cot death has decreased by 60 to 70% in the last 10 years. The largest decrease has been following the Back to sleep campaign in 1991. The epidemiology of cot death now emphasises its association with poverty and smoking in the home. The compassionate reception of the 'cot death' baby and his family in the Accident and Emergency department is the first step in enabling families to come to terms with the grief that the death produces. Accident and Emergency staff can facilitate the early grieving process by an understanding of the family's needs and the provision of appropriate information.

Physician recognition of hypochondriacal patients.

To examine primary care physician recognition of hypochondriacal patients, we identified a series of such patients in a general medicine clinic using the Whiteley Index. Clinic physicians made blind global ratings of severity of physical disease and unreasonable fear of illness (hypochondriasis) and completed a checklist of somatizing characteristics. Patient records were audited for diagnoses, laboratory tests, consultations, and medications prescribed. Twenty-nine (14%) of 210 patients scored above an established cutoff on the Whiteley Index. These hypochondriacal patients were rated by clinic physicians as more hypochondriacal and were more often given psychiatric diagnoses. Also, clinic physicians identified more somatizing features among hypochondriacal patients including their own reaction to them. This recognition of hypochondriac characteristics may have contributed to better management but may need to be raised to the diagnostic level for maximum benefit.

Influence of salinity on copper and azide toxicity to larval topsmelt Atherinops affinis (Ayres).

Performance of a 7-d growth and survival toxicity test protocol using larval topsmelt, Atherinops affinis (Ayres), was evaluated for copper chloride and sodium azide at representative estuarine salinities. Results showed that topsmelt are amenable to toxicity testing at estuarine salinities ranging from 5 to 34/1000 since control survival was 100% in all toxicity tests. Sensitivity to both toxicants increased at lower salinities, with the LC50s for copper ranging from 205 micrograms/L at 34/1000 to 44 micrograms/L at 10/1000, and those for sodium azide ranging from 54 mg/L at 34/1000 to 7 mg/L at 5/1000. Larval tissue osmolality decreased with increasing copper concentration relative to control fish. Copper uptake was not affected by changes in salinity. This suggests that increased sensitivity to copper was due, in part, to the increasing physiological challenge of osmoregulation. It is also possible that cupric ion concentration increased at lower salinities, resulting in reduced larval survival. It is hypothesized that increased sensitivity to azide at lower salinity was due to the interaction between azide toxicity and increasing osmotic challenge. A second experiment with azide showed that larval acclimation time did not affect the interaction between salinity and azide toxicity.

One-year follow-up of medical outpatients with hypochondriasis.

To examine the diagnostic stability and outcome of hypochondriasis, the authors followed 50 patients with this disorder and 50 age- and sex-matched control subjects after 1 year. After 1 year, two-thirds of the subjects continued to meet criteria for hypochondriasis, and the remaining third had persisting hypochondriacal symptoms. The hypochondriacal subjects were improved on most measures but still differed from the control subjects with regard to attitudes, perceptions, and behaviors that had distinguished them initially. More severe symptoms, longer duration of illness, and coexisting psychiatric illness were predictive of a worse outcome. The data indicate that the diagnosis of hypochondriasis is stable over time, and that, although symptoms wax and wane, characteristic features persist. The findings underscore the importance of diagnosing and treating hypochondriasis in medical outpatients.